Flexible stay-bolt.



B. E. D. STAFFORD FLEXIBLE STAY BOLT.

APPLICATION FILED APR. 1, 1914.

1,1 19,651 Patented Dec. 1, 1914.

\ I Q, 624 IZVENTOR 2 Attorney UNITED STATES PATENT OFFICE.

BENJAMIN E. 'D. STAFFORD, 0F PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO FLANNERY BOLT COMPANY, OF PITTSBURGH, PENNSYLVANIA.

FLEXIBLE STAY-BOLT.

Application filed. April 1, 1914.

To all whom it may concern:

Be it known that'I, BENJAMIN E. D. STAF- FORD, of Pittsburgh, in the county of Allegheny and State of Pennsylvania, have invented certain new and useful Improvements in Flexible Stay-Bolts; and I do hereby de clare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to an improvement in flexible stay bolts.

The inspection of stay bolts within fixed periods is mandatory and to inspect and test them the heads of the bolts must be exposed for tapping and turning. lVith the stay bolts now in use, the head of the bolt is mounted in a sleeve and is covered by a cap screwed to the sleeve. Under constant pressure and excessive heat, the cap joint at times becomes dry and sticks to the sleeve forming what is termed a rust joint, especially when the cap threads are not lubricated. This formation of rust on the threads connecting the cap and sleeve retards removal of the cap, henceit is usually necessary to loosen the cap by striking it with a hammer, which frequently results in fracture or injury to the cap or sleeve. Again where the cap is stuck fast, the efforts to unscrew it result at times in loosening the connection between the sleeve and the outer sheet.

The object of the present invention is to provide for the quick and ready inspection of the stay bolt proper without injury to the parts in which the head of the bolt is mounted, and it consists in the parts and combination of parts as will be more fully explained and pointed out in the claims.

In the accompanying drawings, Figure 1 is a view in side elevation of one embodiment of my invention; Fig. 2 is an end view of the same; Fig. 3 is a view in longitudinal section; Fig. 4 is a view in elevation of the plug detached; Fig. 5 is a similar view of the cap; Fig. 6 is a view in section of a slightly'modified construction and Fig. 7 is an end view partly in elevation and partly in section of the construction shown in .Fig. 6.

1 represents the bolt preferably provided with a substantially spherical head 2, hav- Specification of Letters Patent.

Patented Dec. 1, 1914.

Serial No. 828,864.

boiler is the sleeve or bushing 5, threaded externally. This sleeve which is preferably drop forgedpr a malleable casting, has a bore or opening at its inner end of greater diameter than the body of the bolt 1, and is made fiarlng so as to permit of a free lateral or rocking movement of the bolt within reasonable limits. This sleeve is designed to receive and house the head 2 of the bolt 1, and 1s provided internally with a seat 6, formed in the arc of a circle concentric with the head 2 of the bolt, against which the head rests and which permits of a universal .movement of the head on its seat during the expansion and contraction of the sheets to which the bolt is connected. The bore or cavity in the sleeve 5, above, or to the outerslde of the seat 6, is of a size sufficient for the free entrance of the head of the bolt, and the sleeve is preferably provided externally, intermediate its ends, with a hexagonal or angular portion 7 for the wrench employed for attaching the sleeve-to the boiler sheet. The extreme outer end of the sleeve 5, is threaded internally to receive the externally threaded plug 8 which is provided with an angular socket 9 for the insertion of a driver, and the side of the sleeve 5 intermediate its outer end and the seat 6, 1s cut away as shown, forming a lateral opening for the insertion and removal of the cap 10, which is shown detached in Fig. 5. This cap is preferably drop forged steel or malleable iron or brass casting, and is circular in shape and is provided with a finger piece 11 by which it may be conveniently handled. This cap forms the outer closure .of the housing for the head of the bolt, and

is preferably concave on its lower face as at 12, and provided on its upper face, adjacent its periphery with a rib '13, within which the inner end of the plug 8 bears. The sleeve 5 is provided with a recessed seat 14 in which the cap 10 rests, and the inner end of the plug fits within, or is encircled by the rib 13 on the cap, hence it will be seen, that, when the cap is locked in place, there can be no possibility of its accidental displace-- ment. The dimension of the cap 10 are slightly less than the depth and width'of the opening in the side of the sleeve, so that the cap may be readily entered, and withdrawn from said sleeve through said opening, and when fully entered it drops into its recessed 51. set e-se saw? F L bolt head housing. With this construction there are no binding stresses on the plug, as the expansive action of the sleeve due to the expanding pressure of the bolt head therein, is outward or away from the plug, hence it is always an easy matter to unscrew or ease up the plug and thus release the cap. By removing the plug and cap the bolt head is exposed for testing by tapping and turning, and if it be found to be intact it can be again housed by inserting the cap and locking the latter in place by the screw plug.

The construction shown in Figs. 6 and 7 is substantially identical with that shown in Fig. 1, except that the sleeve is slotted at diametrically opposite points thus leaving an outer ring 15 connected to the sleeve proper by two posts 16 integral with the sleeve and ring. With this latter construction the cap may be entered and withdrawn from either side. With this improvement the plug backs up and reinforces the cap and takes all outward pressure of the bolt head thereagainst which would occur under collapsing strains.

If desired the threaded upper end of the sleeve may have oil grooves formed in the threads as shown in dotted lines in Fig. 6. the ends of the grooves being exposed so as to permit oil to be introduced to loosen up the plug.

Instead of making the outer end of the sleeve integral with the sleeve as shown in full lines in Figs. 3 and 6, it may be made separate from the sleeve and screwed to the latter as shown by dotted lines in Fig. 3.

By the term plug I do not necessarily mean a solid block such as I have shown, as it may be ring shape with an open center. It is also evident that other changes might be made without departing from the spirit of my invention hence I would have it understood that I do not confine myself to the details shown but consider myself at liberty to make such changes as may fall within the scope and intent of the claims.

Having fully described my invention what I claim as new and desire to secure by Letters-Patent, is

1. In flexible stay bolt construction, the combination of a sleeve adapted for attachment to a boiler sheet and having a seat for a stay bolt head and an internal seat for a closure, an internally threaded member at the outer end of the sleeve, an externally threaded member mounted in the internally threaded member, and a closure engaged by said externally threaded member adapted to rest on said closure seat, the said closure being-removable from the sleeve without wholly disconnecting the externally threaded member from the internally threaded member.

2. In flexible stay bolt construction, the combination of a sleeve adapted for attachment to a boiler sheet, and having a seat for a stay bolt head, a cap seated on the sleeve and forming a closure for the same and a member at the outer end of the sleeve and engaging the cap for locking the latter in place and also forming a backing or reinforce for the same, the said cap being adapted to be removed and replaced without removing the member at the outer end of the sleeve.

3. In flexible stay bolt construction, the combination of a sleeve adapted for attachment to a bOiler sheet and having a seat for a stay bolt head, a removable cap forming a closure for the sleeve, and a screw plug for locking the cap in place the said plug being supported against the outer face of the cap and in line with the bolt and the said cap being removable from the sleeve without disconnecting the screw plug from the sleeve.

4. In flexible stay bolt construction, the combination of a sleeve adapted for attachment to a boiler sheet and having a seat for a stay bolt head, a removable cap forming a closure for the sleeve and an externally threaded member supported against the outer face of the cap for locking the latter in place the said threaded member being located in line with the bolt and the said cap being removable from the sleeve without disconnecting the externally threaded member from its support.

5. In flexible stay bolt construction, the combination of a sleeve adapted for attachment to a boiler sheet and having a seat for a stay bolt head, a movable plug carried at the outer end of said sleeve, and a removable cap located intermediate the plug and seat for the stay bolt head, the said cap being removable without disconnecting the plug from the sleeve.

6. In flexible stay bolt construction, the combination of a sleeve adapted for attachment to a boiler sheet and having a seat for a stay bolt head, a screw plug carried at the outer end of said sleeve and a removable cap located intermediate the screw plug and the seat for the stay bolt head, the said cap being held in place and reinforced by the plug and adapted to be removed from the sleeve without disconnecting the plug from the sleeve. 1

7. In flexible stay bolt construction the and replaced in the sleeve without disconnecting the screw plug from its support on the sleeve.

8. In flexible stay bolt construction, the combination of a sleeve having a seat for a stay bolt head and a lateral opening intermediate said seat and the outer end of the sleeve, a cap adapted to be inserted through such lateral opening and form a closure for the sleeve and cap securing means carried by said sleeve and adapted to bear against the outer face of the cap and lock the latter in place.

9. In flexible stay bolt construction, the combination of a sleeve having a seat for a stay bolt head and a lateral opening inter mediate said seat and the-outer end of the sleeve, a cap adapted to be inserted through the lateral opening in the sleeve and form a closure for the sleeve and a screw plug screwed to the outer end of the sleeve and adapted to bear against the outer face of the IO. A stay bolt structure comprising a sleeve having a seat for the head of the bolt, an unyielding metal cap forming a closure for the sleeve and a screw threaded member, carried at the outer end of the sleeve and forming a reinforce for the cap.

11. In a flexible stay bolt structure, the combination of a sleeve having a seat for the head of the bolt, the outer end of the sleeve being internally threaded, a rigid unyielding cap adapted to form a closure for the sleeve and externally threaded cap securing means engaging the internally threaded outer end of the sleeve and adapted to bear against the outer face of the cap.

12. In flexible stay bolt construction, the combination of a sleeve having a seat for the head of the bolt, an external angular portion, an outer internally threaded end, and a lateral opening, a cap adapted to be inserted and removed through said lateral opening and form a closure for sleeve and externally screw threaded means engaging the internally threaded outer end of the sleeve and adapted to engage the cap and lock the same in place.

13. In flexible stay bolt construction, of a. sleeve adapted for attachment to a boiler sheet and having a seat for the head of a stay bolt, cap securing means adjustably carried at the outer end of said sleeve and a cap forming a closure for the sleeve, the said cap adapted to be placed in and removed from position Without removing the cap securing means.

14. In flexible stay bolt construction, the combination a sleeve adapted for attachment to a boiler sheet and having an internal seat for the head of a stay bolt, a cap forming a closure for the sleeve, and means for locking the cap in place, the said sleeve and locking means being constructed to permit the cap to be removed and replaced without removing the cap locking means.

15. In flexible stay bolt construction, the combination of'a sleeve adapted for attachment to a boiler sheet and having an inter,- nal seat for the head of a stay bolt, a cap forming a closure for the sleeve and provided on its outer face with a bead or rib, and a plug for locking said cap in place, the portion. of the plug contacting with the cap engaging the latter within the bead or rib whereby the cap is prevented from lateral displacement.

In testimony whereof, I have signed this specification in the presence of two subscribing Witnesses.

BENJAMIN E. D. STAFFORD.

Witnesses:

EDWINYA. RYCE,

HOWAID O. CAPPEL.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of .Patents, Washington, D. 0." 

